Steam-generator



UNITED STATES PATENT OFFICEe THOMAS L. STURTEVANT AND THOMAS J. STURTEVANT, OF FRAMINGHAM, MASSACHUSETTS.

STEAM-G EN ERATOR.

SPECIFICATION forming part of Letters Patent No. 480,417, dated August 9, 1892.

Application filed January 16, 1892. Serial No. 418,324. (No model.)

To all whom it may concern:

Be it known that we, THoMAs L. STURTE- VANT and THOMAS J STURTEVANT, citizens of the United States, residing at Framingham, in the county of Middlesex and State of Massachusetts, have invented certain newand useful Improvements in Steam-Generators; and we do hereby declare the following to beafull, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same, reference being had to the accompanying drawings, and to the figures of reference marked thereon, which form a part of this specification.

This invention relates to Steam-generators; and it consists in the peculiar disposition of the steam-generating tubes.

A marked feature in this Steam-generator is embodied in the arrangement of opposite end headers or steam and Water tight receptacles and in the several series of cross-tubes for the generation of Steam. These tubes, as will be seen, may be curved or straight and disposed in groups alternately oppositely inclined. The lower ends of one group connect with the corresponding part of that header in which they are located, while the upper ends thereof enter the corresponding portion of the opposite header.

The drawings herewith annexed represent in Figure 1 a front sectional elevation of a Steam-generator having straight end headers embodying our invention. Fig. 2 is a Vertical transverse section. Fig. 3 is a front sectional elevation of a generator in which the upper end portions ofthe headers are bent and converge. Fig. 4: is a similar View, in which both ends of the headers converge to adapt them to the use of straight cross-tubes. Fig. 5 is a modified View in end elevation of a generator in which the headers are straight but incline toward each other. Fig. Gis a sectional View of a cross-tube containing an apertured circulating-pipe.

In the above-described drawings,2 2 represent end headers or water-legs, which are upright hollow receptacles steam and water tight. The grate-bars are shown at 3, the feed-pipe at 4, a blOW-Off at 5, and a connecting-pipe 6 between the headers at their base. This pipe is located outside of the fire-box and at the rear of the generator proper. Figs. 1 and 2.)

A prominent point in this Steam-generator,

(See

as shown in Fig. 1, consists in the combinaupon the form of the headers, and are united therewith by expanding the ends. Each alternate group has the same iuclination, but oppositely of the other, and co-operating groups which compose the steam-generating surface. These tubes efiect a good exchange of the water between the two headers when the fire is applied and insure a rapid circulation. Further, their position directly above the fire presents a highly-effective heatingsurface, while the greater the angle of inclination of these cross-tubes the nore rapid will be the circulation and exchange of water between the headers. In practice the exchange of Water is so nearly equal between the headers that no other Water connection has been found necessary; but we prefer to put in one or two cross-connection pipes 6, before mentioned, making a water-circuit outside of the fire and insuring an equal water-level. difficulties occasioned by the unequal expansion of said tubes are avoided.

The Various drawings show different forms of headers designed to facilitate the construction of the generators and in some instances permit the cross-tubes to be straight, as shown in Fig. et, and are to be preferred, since they can be cleansed more readily than the curved ones.

By curving the cross-tubes 7 7 all These generators are adapted to carry a water-level; hence the employment of a watergage 8 and try-cocks 9. The steam-space of the generator by means of the construction indicated in Figs. l and 2 is contained in the connecting transverse pipes 10 10, while in Figs. 5

IOO

14 are arranged at the rear end of the generater. Said tubes are arranged in a Vertical series at the rear end of the inclined tubes, and besides providing steam and water space increase the heating-surface of the generator and incidentally perform the important duty of proteeting the end of the easing from the most intense heat of the fire, thus insuring a cooler interior. These several tubes 14 are fitted with internal circulating-pipes 15. The latter are formed with an opening 16 midway of their length, which permits the water to enter both ends of the said pipe and be discharged from either extremity of the cross tube 14. Inasnucl as the cooler water of the headers must run into the circulating-pipes and be discharged from the central opening 16 into the outer tubes to take the place of the hotter water driven out toward the headers by the heat from the fire there are no opposing currents set up within either tube, the ater cnrrents performing a steady and reguiii' circuit.

The operation of this generator, as hereinbefore described, is as follows: A fire is made upon the grate under the Steam-tubes and the products of eombustion rise up between the headers and the Spaces between the tubes directly to the chimney, (shown at 17.) The tubes thus heated being previously supplied with water to the proper level, such Water as is contained in the several groups of crosstubes 7 7 immediately becomes heated and commences to rise and fiows over into the headers, while cold water enters at their lower ends from said headers. Thus a rapid exchange of water between the headers is established as the heat from the fire increases.

The Steam formed in the cross-tube 7 is lib of the generator, they afiord in marine boilers protection to the boat, arresting the effects of a hot fire in two directions.

What we desire to claim is- 1. In a Steam-generator, the combination,

with opposite headers constructed to form water tightreceptacles, of groupsof inclined tubes arranged in series and com nunicating at ther lower ends with the lower part of one header and at their upper ends with the upper part of the opposite header, and horizontal crosstubes arranged in Vertical series at the rear of the said inclined tubes, substantially as set forth.

2. In a steamgenerator, the combination, with opposite headers, of oppositely-inclined groups of cross-tubes communicating at their lower ends with the lower part of one header and at their upper ends With the upper part of the opposite header, and a series of horizontal cross-tubes forming transverse conmunications between said headers, each of said horizontal tubes having an interior cireulation-pipe.

3. In Steam-generators, the combination, with opposite headers and the oppositely-inclined alternate groups of crossed tubes, of a series ot' horizontal cross-tubes uniting the headers' and an interior eirculating-pipe formed with an opening midway of its length and located within each horizontal tube, substantially as explained.

4. In asteam-generator,thewater-tight headers, the oppositely-inclined alternate groups of curved steam-generating tubes, and one or more steam-collecting tubes which interconneet said headers, combined with a series of horizontal cross-tubeslikewise uniting opposite headers and interior circnlating-pipes apertured nidway of their length and contained one within each cross-tube, substantially as set forth.

5. In a Steam-generator, the opposite watertight headers formed with their corresponding ends bent toward each other, combined with one or more groups of straight crossed 'tubes alternately oppositely inclined, which unite said headers, the exterior circulatingpipe 6, one or more steam-eollecting pipes, and a series of cross-tubes, each adapted to contain a eirculating-pipe formed with a lateral aperture about midway of its length, all operating substantially as explained.

In testimony whereof we affix our signatures in presence of two Witnesses.

THOS. L. STURTEVANT. THOMAS J. STURTEVANT. Witnesses:

H. E. LODGE, FRANCIS C. STANWOOD. 

